Apparatus and method for scanning an object

ABSTRACT

A method for scanning an object is provided. The method involves placing the object on a scanning platform. The scanner has a plurality of cameras positioned around the object to be scanned. The scanned object can be a foot, among other things, and the scanner is positioned at a predetermined incline so that the foot is evenly supported. A positioning system including at least one sensor is used to determine if the foot is located within a predetermined scanning area. The method can be used to measure foot dimensions for the production of shoe lasts and construction of shoes. The method can be used in a system for selecting shoes that properly fit.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is a divisional of U.S. patent application Ser.No. 11/298,171 having a filing date of Dec. 10, 2005, now allowed, whichis a continuation-in-part of U.S. patent application Ser. No. 10/915,900having a filing date of Aug. 11, 2004, now U.S. Pat. No. 7,557,966, theentire disclosures of which are incorporated herein by reference.

FIELD OF THE INVENTION

This invention relates generally to method for scanning an object. Moreparticularly, this invention relates to a method for scanning thethree-dimensional shape of a foot.

BACKGROUND OF THE INVENTION

The footwear industry has become a large, specialized, and competitiveenvironment. The industry has long-established methods of operation, oneof which is to determine shoe size based upon the length and width ofthe foot. Shoe lasts, which are solid forms upon which shoes areconstructed for each shoe size, are used in the manufacture of shoes.Therefore, properly sized lasts are essential for a successful shoeline. Properly fitting shoes are always important to consumers, but fitcan be particularly important for golfers who wear relatively stiff golfshoes over varied terrain for relatively long periods of time and invaried weather conditions. Golfers often experience blisters caused bypoorly fitting golf shoes. Poorly fitting shoes can also affect thegolfers' hitting performance by not providing a stable base for theirfeet during golf swings. Thus, it is important to obtain the bestfitting shoes to minimize such problems.

Various mechanical techniques have been proposed in the past forobtaining foot measurements. For example, most shoe stores commonly usea foot measuring scale known as the Brannock device, produced by theBrannock Device Company of Syracuse, N.Y. This device consists of ametal base plate with several sliding scales. It measures the length andwidth of the foot to determine an appropriate shoe size. One problemassociated with the Brannock device is that its foot measurements areonly two dimensional in nature, measuring an absolute length from heelto toe and the width. This method fails to take into considerationfactors such as type of heel, for example, bony versus padded; shape ofthe toes, for example, square versus tapered; insole arch; and othercharacteristics. This device also fails to measure characteristicsassociated with medical problems such as bunions, which require largershoe sizes to accommodate abnormalities of the foot.

Some systems use cameras to determine the characteristics of the foot.U.S. Pat. No. 5,911,126 to Massen discloses a method and arrangement fordigitizing three-dimensional sensing of the shape of bodies or bodyparts. The data can be used for automated fabrication of a shoe last,bedding or foot molding, for example. This system uses an elasticenvelope worn over the foot/body part during imaging by several camerassurrounding the foot/body part. The envelope carries a high-contrastpattern that allows for digitizing of the image. This method requiresthat a high contrast pattern is applied onto the bodies or body parts toprovide the contrast for digital manipulation.

Other systems have proposed the use of laser beam measurement todetermine the characteristics of the foot, as disclosed in U.S. Pat. No.4,745,290 to Frankel et al.; U.S. Pat. No. 5,164,793 to Wolfersberger etal., and U.S. Pat. No. 5,237,520 to White. In the Frankel andWolfersberger references, the heel area is not measured. In the Whitepatent, the dimensions of the upper foot are not obtained. Since allareas of the foot are important for a proper fit, omitting these areasis undesirable. Additionally lasers, which are structured light sources,do not illuminate the entire foot at once. The foot is typically paintedline-by-line, sequentially until the entire foot is painted. This methodof illumination takes time and requires a control mechanism for thelaser. The foot must also remain stationary during this time period.Furthermore, laser systems are expensive.

U.S. Pat. No. 6,633,326 to Fukumoto describes an image system, wherebyan image pick-up head having a CCD camera mounted thereon capturesimage(s) of a foot. The image pick-up head is mounted on an ellipticalrail surrounding the foot. The reference also discloses a particulararrangement of signal cable and auxiliary cable to prevent entanglement.The foot needs to remain stationary for a relatively long time for thecamera to image all sides of the foot. This reference does not disclosehow the image(s) can be processed to create a three-dimensional model ofthe foot.

Hence, there remains a need in the art for an apparatus and method foraccurately measuring feet for production of lasts and selection ofproper fitting shoes, among other uses.

Further, in obtaining an image from a scanning system, it is oftendesirable to position the object within a very specific field of viewfor optimal image capture. Hence, there remains a need in the art for anautomatic object placement verification system for use with an apparatusand method for accurately measuring feet for production of lasts andselection of proper fitting shoes among other uses.

SUMMARY OF THE INVENTION

The present invention is directed to a method for establishing aposition of an object to be scanned, comprising the steps of:

(i) placing the object on a scanning platform, wherein the scanningplatform includes a predetermined scanning area having at least onesensor;

(ii) obtaining a signal from the sensor; and

(iii) analyzing the signal to determine if the object is within thepredetermined scanning area.

The sensor may be positioned either outside of or within thepredetermined scanning area. The sensor may comprise apressure-resistive sensor. If the object is not positioned within thepredetermined scanning area, a signal may be sent to a user interface toreposition the object. The interface may receive directional guidancefor repositioning the object. In one version, the method involvesdetermining if the object is positioned on a sensor or at least aportion of the object is placed on a plurality of sensors.

BRIEF DESCRIPTION OF THE DRAWINGS

In the accompanying drawings, which form a part of the specification andare to be read in conjunction therewith, like reference numerals areused to indicate like parts in the various views:

FIG. 1 is a perspective view of a scanner in accordance with the presentinvention;

FIG. 2 is a side view of the scanner is FIG. 1;

FIG. 3 is a perspective view of the cameras and processing equipmentcontained within the scanner of FIG. 1;

FIG. 4 is a top view of the cameras and processing equipment of FIG. 3;

FIG. 5 is a cross-sectional view along line 5-5 in FIG. 4;

FIG. 6 is a cross-sectional view along line 6-6 in FIG. 4;

FIG. 7 is a front view of the printed circuit board (with certaindetails omitted for clarity) located behind one of the camera pairsillustrating the triangulation technique and calibration technique;

FIG. 7A is a schematic view showing an angle defined by the camera pairsand the object to be scanned;

FIG. 7B is a schematic view of overlapping FOV between the camera pairs;

FIG. 8A is an exemplary portion of a triangulated image in gray scale;

FIG. 8B is an exemplary portion of FIG. 8A in binary black/white scale;

FIG. 9 is an exemplary point cloud representative of a scanned foot;

FIG. 10 is a top view of an alternate embodiment of the cameras andprocessing equipment of a scanner in accordance with the presentinvention showing the sensors and processing equipment of an automatedfoot placement system;

FIG. 11 is a flow chart showing an exemplary method for scanning a foot;and

FIG. 12 is a flow chart showing an exemplary method for determiningand/or correcting foot placement.

DETAILED DESCRIPTION OF THE INVENTION

Referring to FIG. 1, scanner 10 comprises a display or monitor 12supported by neck 14 on housing 16. Display 12 preferably has touchscreen capability to interact with users. Neck 14 can be telescopic sothat monitor 12 can be raised or lowered. Housing 16 defines cavity 18,which is sized and configured to receive an object to be scanned. Anythree-dimensional object can be scanned, and cavity 18 can be enlargedto accommodate objects of any size. The present invention is describedbelow using a foot; however, the present invention is not limited to anyparticular scanned object.

As shown in FIG. 2, housing 16 is preferably orientated at an inclinerelative to a surface supporting the scanner. The inventors of thepresent invention have determined that a foot inclined at apredetermined range of inclination angles exerts even pressure on thefoot. In other words, at the preferred inclination the foot exerts evenpressure on the heel and the balls. Advantageously, no part of the footis unevenly deformed or squashed so as not to cause improper footmeasurements. For persons weighing between 100 lbs and 250 lbs, thepreferred inclination angle ranges from about 12° to about 20°, morepreferably about 14° to about 18°, and most preferably about 16°.

Referring to FIGS. 3-6, inside housing 16 and supported on platform 20are camera pairs 22 comprising cameras 24, 26, and central processingunit or equipment (CPU) 28. Platform 20 may also support a hard drive,input/output (I/O) boards, USB boards, telephone modem, wirelesscommunication devices, display units, and the like. Camera pairs arepreferred, because the pairs provide depth perception to the image,similar to binoculars and human/animal eyes. The processes formanipulating the data from the images taken from the camera pairs arediscussed below. Although the present invention is described herein withcameras 22 arranged in pairs, single cameras can also be used, insteadof pairs with the present invention. For single cameras, depthperception can be obtained by using adjacent cameras as pairs. A singlecamera can be a part of two pairs with its two adjacent cameras. Asingle camera can also form a pair with a non-adjacent camera.Alternatively, a single camera may be rotatably mounted on a supportsuch that the camera may be toggled between two positions so as tosimulate having a pair of cameras. For example, a camera mount may beelectronically controlled to take a picture in a first orientation, movethe camera a specified distance, such as through a predetermined anglein any direction, to a second orientation, and then take a secondpicture in the second orientation. Preferably, the specified distance issmall, such as less than about 5 degrees.

Unique to the present invention, unstructured light is used toilluminate the scanned object covered by a textured surface.Unstructured light includes, but is not limited to, sunlight, diodes,fluorescent light, and incandescent light, among others. Unstructuredlight broadly includes any light sources that don't have controlledfrequencies. The entire scanned object can be illuminated at once,thereby eliminating the time consuming step of sequentially painting anobject line-by-line with a structured laser beam. The optical patternnecessary for analyzing the scanned object is provided by a texturedsurface covering the scanned object. In accordance with one aspect ofthe present invention, the textured surface can be a textile sockcovering a foot. Preferably, the sock fits snugly over the foot andwithout the sag rings around the ankles, so that a proper footmeasurement can be achieved. Suitable socks can have any color orpattern and preferably have one color. If the socks have multiplecolors, preferably the colors do not substantially contrast each other.The socks can be athletic socks or dress socks, and can be made fromwoven, non-woven, stitch-bonded non-woven or knit textiles.

At least three camera pairs can be deployed to image the foot, includingtoe camera pair 32 and two side camera pairs 34. These three camerapairs can image the top and sides of the foot. Alternatively, the twoside camera pairs 34 can be used along with a positioning device, suchas a heel stop or toe stop (not shown). Any number of cameras can bedeployed, and preferably seven camera pairs are used, as shown in FIGS.3-6.

As best shown in FIG. 4, one of the camera pairs is preferably toecamera pairs 32, and the remaining camera pairs are preferably evenlydistributed as shown to capture all surface areas of the foot. Two ofthe remaining camera pairs are preferably side cameras 34.Alternatively, camera pairs 22 are not evenly spaced apart, so long astheir fields of vision (FOVs) overlap each other so that all surfaceareas of the foot are imaged. Camera pairs 22 can be evenly, angularlyspaced apart, while the distances to the scanned object are uneven, orvice versa. In accordance with another aspect of the present invention,the FOVs do not necessarily overlap each other, but each FOV images adistinct part of the foot to measure the size of the foot and/or to forma last representative of the foot. In the art of shoemaking, twelveseparate measurements of the foot are necessary to construct a last.Hence, each camera or camera pair can measure one or more measurementsto make a last.

To obviate the need to focus the cameras prior to imaging, the cameraspreferably have relatively small apertures. The aperture can be as smallas F-22. Smaller aperture provides a relatively long distance withinwhich no focusing is necessary. In one embodiment, an F-8 aperture isselected for the cameras. This aperture provides a fixed focus fromabout 6 inches to 14 inches away from the lenses. Preferably, thescanned object is positioned within this fixed focus distance. Camerapairs 22 may have different aperture sizes.

Suitable cameras include, but are not limited to, CMOS (complimentarymetal-oxide sensor) digital or electro-optical cameras. Suitable CMOScameras are commercially available from OmniVision Technologies, Inc. ofSunnyvale, Calif.; Micron Technology, Inc., of Boise, Id.; and Veo, Inc.of San Jose, Calif., among others. Each of the cameras has a lens thatdirect light to strike an array or panel of image sensor photo-sensitivecells or pixels. Each photo-sensitive cell or pixel is aphoto-transistor which converts light into a voltage signal representingthe light level. The voltage signal is stored as analog information andthen digitized by an analog-digital-converter. Alternatively, CCD(charge coupled device) cameras can be used. CMOS and CCD cameras arewidely available as consumer digital cameras. Analog cameras can also beused, so long as the image can be digitized thereafter, for example, bydigital scanning.

Referring to FIG. 5, where a front view of camera pairs 22 is shown,cameras 24 and 26 of camera pairs 22 are supported on front face 36.Front face 36 also protects the electronics on the printed circuit board(PC) 38. As shown in FIG. 7 with other details omitted for clarity,directly behind each camera 24, 26, is the photo-sensitive panel 24′,26′, respectively. Preferably, photo-sensitive panels 24′, 26′ arepositioned parallel or co-planar to each other. According to one aspectof the invention, each photo-sensitive panel comprises a two-dimensionalarray of 1280 pixels by 1084 pixels to give each panel about 1.38megapixels. In one embodiment, the cameras are black and white cameras,and each pixel, when exposed, records a gray value having a numericalrepresentation of 0-255 on the gray scale. Alternatively, color camerascan be used. During manufacturing, each panel 24′, 26′ is fixedlyattached to PC 38 by molten solder. Due to its relatively highviscosity, the surface tension of the molten solder keeps the panelsoriented substantially parallel to PC 38. As the solder hardens,photo-sensitive panels 24′, 26′ are fixed to PC 38.

To compensate for any misalignment from this parallel arrangement, eachPC 38 is calibrated. Referring again to FIG. 7, cameras 24, 26 (notshown) are mounted on top of photo-sensitive panel 24′, 26′ in front ofcalibration board 40. Calibration board 40 comprises a plurality ofmarkings 42. Each marking 42 is preferably unique from each other andthe locations of markings 42 on calibration board 40 are known.Calibration board 40 is located parallel to PC 38 at known distances, sothat the location of each marking 42 in three-dimensional space relativeto cameras 24, 26 is known. Each marking 42 is imaged by cameras 24, 26via focal points 24 f, 26 f, respectively. Each marking is exposed atdifferent locations on photo-sensitive panels 24′, 26′. By comparing thelocations of each marking on photo-sensitive panels 24′, 26′ to eachother and to the known location of corresponding marking 42 oncalibration board 40 using the triangulation technique discussed below,any misalignment from the parallel orientation can be detected.Calibration board 40 is preferably positioned at three differentlocations from PC 38, for example, 6 inches, 11 inches and 14 inchesaway from PC 38, during calibration. Corrections to restore the parallelarrangement can be calculated and stored on a memory on each PC 38.

One readily apparent advantage of the present invention is that byplacing both photo-sensitive panels and both cameras on a single PCboard it is easier to arrange the photo-sensitive panels to be parallelor co-planar to each other. As used herein, the term parallel includesboth parallel and co-planar.

As best shown in FIG. 5, the cameras in pairs 22 are offset with respectto each other, that is, they do not align vertically or horizontallywith each other. In one aspect of the invention, cameras 24 and 26 areoffset about 0.5 inches in the vertical direction and about 1.0 inchesin the horizontal direction relative to platform 20. Any offsettinggeometry can be utilized, although the offset is preferably betweenabout 0.5 inches and 1.0 inches in any direction. The offsettinglocation enhances the depth perception of the camera pairs.

The method of locating a single point or pixel in three-dimensionalspace by both cameras is based on binocular triangulation methodology.Referring again to FIG. 7, an arbitrary point “a” in three dimensionalspace (x, y, z) or (R, Ø, θ) creates image point 24 a on panel 24′ andimage point 26 a on panel 26′. In one example, point “a” can be anypoint on the textured surface of the sock covered foot. The relativelocations of these image points are different on the photo-sensitivepanels. In other words, image points 24 a and 26 a are located atdifferent relative positions on photo-sensitive panels 24′ and 26′. Tomatch image points 24 a to image point 26 a and to represent point “a”in three-dimensional space, in one embodiment a PC processor, which ispreferably located on PC 38, searches and matches neighboring points orpixels in the vertical and horizontal directions. When the neighboringhorizontal and vertical pixels match each other, then a match is foundfor image point 24 a and image point 26 a. When the contour of the footor the scanned foot is sharp, for example, around the ankle or greaterthan 45°, or when point “a” is located near the edge of the camera lens,image points 24 a, 26 a may not match each other. Unmatched points inthe images are relatively few in numbers, and some images do not haveunmatched points.

Binocular triangulation also provides depth perception, because anobject is viewed by two lenses (or eyes) and the two images are joinedto create a single image. The depth or distance between the scannedobject (for example, the scanned foot or calibration board 40) andcameras 24, 26 can be determined from the distance between matchedpoints 24 a and 26 a, as measured on the PC board and the angle betweenline 24″ connecting point 24 a to point “a” and line 26″ connectingpoint 26 a to point “a.” Hence, by employing camera pairs the locationof any pixel representing a point on the scanned foot inthree-dimensional space relative to the camera pairs is known. Also, asdiscussed above binocular triangulation can be used with single camerasinstead of camera pairs, when adjacent (or non-adjacent) single camerasare paired up for triangulation.

As shown in FIG. 7A, cameras 24 and 26 are positioned relative to eachother such an incident angle, α, is defined between image point 24 a andimage point 26 a and point a on the object to be scanned. Preferably,incident angle a is less than about 90 degrees and preferably less thanabout 45 degrees so that the overlap 25, shown in FIG. 7B of the FOV ofcamera 24 and the FOV of camera 26 is maximized. The overlap of thesefields of view is preferably greater than about 60%, and, morepreferably, at least about 80%, although any amount of overlap may beused in the present invention. Overlapping FOVs and incident angle a areexemplary factors that can be utilized to control the offset orpositions of camera pairs.

To minimize calculation errors, after image point 24 a is matched toimage point 26 a, the distance between point “a” in three-dimensionalspace as seen by camera 24 and the same point “a” as seen by camera 26is calculated. Optimally, this distance should be as small as possible,and preferably it should approach zero. If this distance is greater thana predetermined threshold, then the PC processor or CPU 28 should returnan error signal. Alternatively, a mid-point is chosen based on thisdistance and point “a” is set or reset to the mid-point. For thepurposes of this application, “mid-point” is considered to be theshortest distance, or the common point, for a camera pair 22. Anyarbitrary point within this distance can be used, for example,one-third, one-fourth, one-fifth or any fraction of this distance, canbe used.

As stated above, each PC 38 preferably has its own processor orcontroller to process the data generated by the cameras and a memorystorage device (such as flash memory, EEPROM, EPROM, RAM, etc.) to storethe raw data as well as the triangulated data of matched points andunmatched points, to store the calibration routine, and to transfer thetriangulated data to CPU 28 for further analysis. PC 38 can communicatewith CPU 28 by radio frequency, serial or parallel port connections,optical fibers, USB, USB-2, among others. USB and USB-2 are thepreferred connection modes due to their high transmission speeds and lowcosts.

After calibration, each PC and camera pair are fixedly attached toplatform 20, such that the positions of the camera pairs are known andshould not change significantly. Each camera pair can image other camerapairs in its FOV to calibrate and measure the relative distance betweenthe cameras. For example, referring to FIG. 4, left side camera pair 34can image right side camera pair 34 and lower right hand camera pair 22can image upper left hand camera pair 22 and toe camera pair 32 to fixtheir positions. The relative positions of the camera pairs to eachother and on platform 20 can be stored in CPU 28.

Since each camera pair 22 has been calibrated so that the positions inthree-dimensional space of the scanned image in its FOV relative to thecamera pair are known, and since the locations of each camera pairrelative to each other on platform 20 in scanner 10 are also known, thelocations of each pixel in three dimensional space representing thescanned foot after the images from each camera pair have been stitchedtogether are also known.

After CPU 28 receives all of the triangulated images captured by thecamera pairs, CPU 28 stitches or otherwise combines these images tocreate a three-dimensional image of the sock-covered foot, e.g., pointcloud. An exemplary image received by CPU 28 is shown in FIG. 8A. In onepreferred embodiment, an area 43 equivalent to 32 pixels by 32 pixels isselected for matching an image to adjacent images. Selected area 43represents a portion of the textured sock imaged by a camera pair.Selected areas 43 are located in the areas where the FOVs of adjacentcamera pairs are overlapping each other. In any selected area 43, eachpixel has a gray scale value from 0 to 255 produced by the black andwhite digital cameras. Zero value can designate white and a 255 valuecan designate black and everything in between represents a differentshade of gray. Hence, a selected area 43 in gray scale in one image canbe searched and matched to a corresponding selected area 43 on anadjacent image. Once a match is made, two adjacent triangulated imagescan be stitched together with the matched selected areas 43superimposing each other.

Since selected area 43 in gray scale requires a significant amount ofmemory storage and processing speed, efficiency and processing speed canbe improved when selected area 43 is converted from gray scale toblack/white or binary scale. A predetermined threshold gray value isselected. Any gray scale value above this threshold gray scale isconverted to black and any gray scale value below this gray scale isconverted to white, as shown in FIG. 8B. After the conversion, one ormore islands 44 are created in selected area 43. The predeterminedthreshold can be the average gray scale or can be any value less than255. When the threshold is low, more islands are created and when thethreshold is high, fewer islands are created. The threshold value canalso be adjusted while scanner 10 is in operation to assist with theimage stitching process. Islands 44 in selected area 43 can be used tomatch an image to adjacent images. To minimize calculation errors,during the island matching process the size and location of islands 44are compared. If the size difference or the location difference exceedspredetermined thresholds, then CPU 28 would also return an errormessage.

During the stitching process, unmatched points from one triangulatedimage are searched for in adjacent triangulated images. If the unmatchedimage points in one image have corresponding matched image points inadjacent images, then the matched points are used. If too many unmatchedpoints remain, CPU 28 may discard the images and instruct the camerapairs to take another set of images of the foot.

From the seven images captured by the seven camera pairs 22, point cloud48 representing the scanned foot can be generated after the seven imagesare stitched together, as shown in FIG. 9. As described above, since therelative and fixed positions of camera pairs 22 on platform 20 inscanner 10 are known, and since the images taken by the camera pairsalso contain three-dimensional positions of each pixel relative to thecameras, point cloud 48 is a three-dimensional representation of thescanned foot.

Alternatively, instead of a point cloud representation a convolutionfiltering process can be applied to the stitched image to provide anembossed view of the foot. Convolution filtering is commonly used incommercially available Photoshop software and is typically used toprovide a clearer outline of the scanned object.

As will be recognized by those in the art, camera pairs 22 mayalternatively include three or more cameras to form camera clusters.Each camera cluster would be positioned in scanner 10 as camera pairs22, as described above. The binocular triangulation method describedabove could be achieved by using signals obtained from any two cameraswithin a camera cluster. For example, a camera cluster may include threecameras, A, B, and C. Cameras A and B could be used to obtain onetriangulation point, Cameras B and C could be used to obtain a secondtriangulation point, and/or Cameras A and C could be used to obtain athird triangulation point. Obtaining several readings from each cameracluster could help to assure the accuracy of the measurements.

Referring to FIG. 10, an exemplary process of scanning both feet isillustrated. Either the right foot or the left foot can be scannedfirst. The first step is to adjust the light level in cavity 18 (seeFIG. 1) where the foot is inserted. Each camera or camera pair has itsown light sensor. Scanner 10 may have its own unstructured lightsources, which can be located between camera pairs 22 or locatedproximate to each camera pair. The amount of illumination generated bythese light sources can be controlled by CPU 28 or by the PC controllersfor the camera pairs depending on the level of light detected by thelight sensors. In one embodiment, the light sources are attached to theunderside of the roof of housing 16.

The next steps are to check all the cameras and to determine whether thefoot is properly placed in cavity 18. If all of the foot, including toesand heel, can be imaged, then the foot positioning is acceptable. Theplacement of the foot can be checked by imaging the foot with some orall of the cameras. Scanner 10 may also optionally include a placementsystem 50 for determining the correct placement of objects withinscanner 10.

In one embodiment, as shown in FIG. 3, placement system 50 may be avisual guide. For example, a pad 30 is defined proximate to the centerof platform 20 to provide visual cues for the correct or preferredplacement of the foot. Pad 30 is preferably printed or colored to show auser a correct placement position.

In another embodiment, as shown in FIG. 10, system 50 may also be anautomatic placement system that includes a plurality of sensors 51, 52,54, 56, 56′, 58, and 58′ for detecting the placement of the object to bescanned, a communication interface board 60 for gathering theinformation from sensors 51, 52, 54, 56, 56′, 58, and 58′ andcommunicating the information to CPU 28, and associated softwaredisposed on a hard surface such as platform 20. In one embodiment,platform 20 is made of aluminum, but it may be made of any rigidmaterial, such as plastic, steel, or the like.

Sensors 51, 52, 54, 56, 56′, 58, and 58′ are preferably pressureresistive sensors or sensor arrays that have low static resistance andhigh resistance when a force is applied thereto. For example, sensors51, 52, and 54 are strip pressure resistive strip sensors and sensors56, 56′ and 58, 58′ are pairs of pad sensors; all sensors are preferablypermanently or removably affixed to platform 20, such as with anadhesive, welding, or printing. As will be apparent to those in the art,any pad sensor pairs, that is, sensors 56, 56′ and 58, 58′, mayoptionally be replaced with a single large sensor. Sensors 51, 52, 54,56, 56′, 58, and 58′ are preferably thin to prevent interference withthe scanning process. In one embodiment, sensors 51, 52, 54, 56, 56′,58, and 58′ have a thickness less than about 2 mm.

Sensors 51, 52, 54, 56, 56′, 58, and 58′ are preferably positioned onplatform 20 such that, as shown in FIG. 10, when a foot is improperlyplaced on platform 20, sensor 52 encounters, a heel of a foot, that is,sensor 52 is powered ON, sensor 51 or sensor 54 encounters the sides ofa foot, and sensor pair 58, 58′ encounters the toes. Similarly, whenproperly placed, sensor pair 56, 56′ encounters a ball of a foot. In aspecial scenario, if a very large foot is properly placed on platform20, sensor 51, sensor 54, and sensor pair 56, 56′ all encounter parts ofa foot. For this exemplary configuration, Table 1 illustrates variousscenarios with combinations of sensors powered on or off and whether ornot this results in a scan or a failure.

TABLE 1 Exemplary Sensor Combinations Sensor Sensor Sensor Sensor Sensor51 52 54 Pair 56, 56′ Pair 58, 58′ Result OFF OFF OFF ON OFF SCAN ON OFFON ON OFF SCAN (assume very large foot) OFF OFF ON ON OFF FAILURE ON OFFOFF ON OFF FAILURE OFF OFF OFF ON ON FAILURE OFF ON OFF ON OFF FAILUREOFF OFF OFF OFF OFF FAILURE

As will be apparent to those in the art, additional permutations existfor even this exemplary embodiment, such as where multiple sensors arepowered ON in combinations not shown in Table 1. In such cases, the scanwill not initiate. Additional configurations of sensors on platform 20are also possible, where the combination of sensors powered ON andsensors powered OFF that result in a scan are determined based upon theactual configuration. For example, sensor pair 56, 56′ may beeliminated, so that a scan will only initiate when no sensors arepowered ON. In another example, only three sensors may be used, a toesensor, a ball sensor and a heel sensor, where a scan will only initiatewhen all sensors are powered ON. In another example, all sensors couldbe placed very close together so that a scan will only initiate when allsensors are powered ON. All possible configurations of sensors arecontemplated by the present invention.

Sensors 51, 52, 54, 56, 56′, 58, and 58′ are connected to communicationsinterface board 60 via connections 64. Connections 64 may be any type ofconnection known in the art, such as electrical wires or filaments,printed leads or a wireless link transmitting information from atransmitter on sensors 51, 52, 54, 56, 56′, 58, and 58′. Similar tosensors 51, 52, 54, 56, 56′, 58, and 58′, connections 64 are preferablyaffixed to platform 20 using any method known in the art. Preferably,connections 64 are adhered to the surface of platform 20, e.g. byadhesives, tapes, etchings, etc.

Communications interface board 60 includes a microprocessor 62 and atleast one digital comparator circuit (not shown) for converting theanalog signals generated by sensors 51, 52, 54, 56, 56′, 58, and 58′into digital information usable by microprocessor 62. Preferably, eachsensor has a dedicated digital comparator circuit. Communicationsinterface board 60 is linked to CPU 28 using any method known in theart, preferably an electrical wire or filament such as connector 66.

Microprocessor 62 may be any microprocessor known in the art capable ofcollecting the digital inputs from the digital comparator circuit(s) andcommunicating with CPU 28. One such suitable microprocessor 62 is an ICMCU flash chip available from Microchip Technology, Inc. of Chandler,Ariz. The communication with CPU 28 may be achieved by any method knownin the art; however, for ease of manufacturing and interchangeability,the communication with CPU 28 is preferably achieved using a networkaccording to the RS-485 standard protocol.

A thin film of material having a visual graphic printed or otherwisedisposed thereupon preferably covers system 50, but at least coverssensors 51, 52, 54, 56, 56′, 58, and 58′. The film may be made of anymaterial known in the art, but is preferably a material such as Mylar®polyester having a non-smearing graphic printed thereupon.

To operate system 50, CPU 28 hosts a system manager software program.This program hosts the user interface program, preferably a graphicaluser interface (GUI), and provides all of the hardware, software, andGUI interaction. This program may be any type of program capable ofperforming these functions, and it may be written in any code known inthe art. For example, the system manager communicates withcommunications interface board 60 to signal microprocessor 62 tointerrogate sensors 51, 52, 54, 56, 56′, 58, and 58′, as well toretrieve the information from sensors 51, 52, 54, 56, 56′, 58, and 58′to be interpreted by CPU 28.

Referring to FIG. 5, one exemplary process of scanning both feet isillustrated. Either the right foot or the left foot can be scannedfirst. The first step is to adjust the light level in cavity 18 (seeFIG. 1) where the foot is inserted. Each camera or camera pair has itsown light sensor. Scanner 10 may have its own unstructured lightsources, which can be located between camera pairs 22 or locatedproximate to each camera pair. The amount of illumination generated bythese light sources can be controlled by CPU 28 or by the PC controllersfor the camera pairs depending on the level of light detected by thelight sensors. In one embodiment, the light sources are attached to theunderside of the roof of housing 16.

To initiate a scan, a user inserts an object such as a foot into scanner10 and inputs through the GUI a signal to begin the scanning process.When the system manager program receives this input, the system managerqueries microprocessor 62 using any type of communication known in theart, such as communications according to the RS-232 standard protocol.The next steps are to check all the cameras and to determine whether thefoot is properly placed in cavity 18. The placement of the foot can bechecked, for example, by following the process shown graphically in FIG.6. First, the system manager sends a signal to the microprocessor toquery sensors 51, 52, 54, 56, 56′, 58, and 58′. If the foot isappropriately positioned within the scanning area, then the systemmanager allows the scan to begin. If the sensors show a resistance, thatis, if the foot is placed on one of sensors 51, 52, 54, 56, 56′, 58, and58′ such that the foot is outside of the appropriate field of view ofthe camera pairs, then the system manager sends a signal to the GUI toinstruct the user to reposition the foot in a certain direction, such asto move the foot forward, backward, or to the left or right or using anyother method as known in the art.

After the foot position is confirmed, the foot can be re-imaged by allthe camera pairs, or the first set of images can be fully processed. Ifthe foot is improperly positioned, then the user is instructed to movehis/her foot before the foot can be imaged.

After the images are taken by camera pairs 22, the images are analyzedto ensure their qualities, for example, whether the number of unmatchedimage points are acceptable or whether the distance between the samepoint “a” seen by camera 24 and camera 26 is within acceptable range.Then the images can be stitched to form a point cloud.

Next, the CPU determines whether the point cloud is acceptable, forexample, whether selected areas 43 between adjacent images can bematched. Then, the point cloud is checked to determine whether itresembles a foot.

After these steps are satisfactorily executed, the other foot is scannedand the same steps are repeated, as shown in FIG. 11. After both feetare scanned, scanner 10 can determine the shoe size for the scannedfeet.

Alternatively, after the feet are scanned/measured, the information isstored or used to make customized shoe lasts.

In accordance with another aspect of the present invention, each scanner10 is provided with a communication device so that it can communicatewith its home base. The communication device can be a telephone modem sothat scanner(s) 10 communicates with home base through telephone lines.Alternatively, the communication device can be wireless, for example,similar to blackberry e-mail devices. After a scanner 10 establishescommunication with home base, it can transfer information stored thereonrelating to the scanned feet to home base, and it can receive commandsor information from home base, for example, marketing informationrelating to the locality where scanner 10 is being deployed. The scannedfeet information transferred to home base can be used to develop newshoe sizes to meet market needs.

In accordance with another aspect of the present invention, each scanner10 has a unique IP address similar to the IP address of a desktopcomputer or laptop, so that home base can distinguish one scanner fromanother and that home base can send targeted information to differentscanners.

While various descriptions of the present invention are described above,it is understood that the various features of the embodiments of thepresent invention shown herein can be used singly or in combinationthereof. This invention is also not to be limited to the specificallypreferred embodiments depicted therein.

1. A method for establishing a position of an object to be scannedcomprising the steps of: (i) placing the object on a scanning platform,wherein the scanning platform includes a predetermined scanning areahaving at least one sensor; (ii) obtaining a signal from the sensor; and(iii) analyzing the signal to determine if the object is within thepredetermined scanning area.
 2. The method of claim 1, wherein thesensor is positioned outside of the predetermined scanning area.
 3. Themethod of claim 1, wherein the sensor is positioned within thepredetermined scanning area.
 4. The method of claim 1, wherein step(iii) comprises determining if the object is positioned on the sensor.5. The method of claim 1, wherein the sensor comprises at least onepressure resistive sensor.
 6. The method of claim 1, wherein step (iii)comprises determining if at least a portion of the object is positionedon a plurality of sensors.
 7. The method of claim 6, wherein step (iii)comprises determining if at least a portion of the object is placed on apredetermined combination of sensors.
 8. The method of claim 6, whereinstep (iii) comprises determining if at least a portion of the object isnot placed on a predetermined combination of sensors.
 9. The method ofclaim 1, further comprising the steps of: (iv) determining that theobject is not positioned within the predetermined scanning area; (v)sending a signal to a user interface to reposition the object.
 10. Themethod of claim 9, further comprising the step of: (vi) providing theuser interface with directional guidance for repositioning the object.